Insulator assembly



March 8, 1955 R. E. LAYMAN INSULATOR ASSEMBLY Filed March 6, 1953INVENTOR floe/" Z l y United States Patent INSULATOR ASSEMBLY Robert E.Layman, Janesville, Wis. Application March 6, 1953, Serial No. 340,879

1 Claim. (Cl. 174-156) The present invention relates to insulatorassemblies and more particularly insulator structures of the type usedfor outside electrical conductors such as, telephone and telegraphwires, the insulator structure being defined by a body portion and a capremovably secured to the body portion, the body portion and the capbeing formed of a plastic material which is substantially unbreakable.

It is, of course, well known that moisture on the wires causes a wetweather cross or a high resistance short between the wires and numerousinsulators have been designed to protect the wires from rain, snow andsleet in an attempt to overcome the problem. Many of these prior unitshave been quite satisfactory but due to the complexity of the modifiedinsulator structure such prior devices have not been fully satisfactory.

Accordingly, an important object of this invention is to provide aninsulator assembly which will protect the wire from moisture and at thesame time be simple in structural detail, positive and efficient inoperation and capable of being easily and inexpensively manufactured.

A further object of my invention is to provide an insulator assembly ofthe type described wherein the insulator consists of but two partscapable of being readily assembled or disassembled with each part beingmade of a plastic material whereby the insulator is capable of use overextended periods of time.

And yet a further object of the invention is to provide an insulatorwherein the assembly is defined by a body portion carried by thecross-arm pin, a cap secured to the body portion and means to anchor thewire between the body portion and the cap so that the wire pulls againstthe pin rather than the cap thereby eliminating slipping, bend andbreakage of the wire.

Still another object of the invention is to provide an insulatorassemblage wherein the cap member so cooperates with the body portion asto permit bending of the wire only in a downward direction therebypreventing breakage of the wire which is caused by the upward anddownward bend in very cold weather.

With the above and other objects in view, the invention consists in thedetails of construction, and in the arrangement and combination of partsto be hereinafter more fully set forth and claimed.

In describing the invention in detail, reference will be had to theaccompanying drawings forming part of this application, wherein likereference characters denote corresponding parts in the several views andin which:

Figure 1 is a perspective view of a cross-arm, partly broken awayshowing the threaded vertical pin.

Figure 2 is a further view in perspective, partly broken away of across-arm with the insulator assembly in position on the threaded pindepicting the manner in which the wire enters and leaves the insulatorassembly.

Figure 3 is a vertical sectional view of the assembled insulator, thethreaded pin of the cross-arm being omitted.

Figure 4 is a view taken along the line 44 of Figure 3, the view lookingin the direction of the arrows, and Figure 5 is a view taken along theline 5-5 of Figure 3, the view looking in the direction of the arrows.

As perhaps best illustrated in Figure 3, the insulator assembly denotedgenerally comprises a body portion 11 and a cap 12. Both the bodyportion and the cap are made of a substantially unbreakable plasticthereby providing an insulator which may be used for an extended periodof time without repair or replacement problems.

The body portion 11 includes a cylindrical base 13 having a longitudinalbore 14 therein, the bore being formed with internal screw threads 15adapted to engage external threads 16 of a vertical pin 17 carried by across-arm 18. Hence, the insulator is easily and readily attached to thecross-arm.

The base 13 is further provided with a horizontally disposed shoulder 19intermediate the upper and lower ends thereof, the shoulder having twopairs of diametrically opposed grooves 20 therein, the grooves beinglocated adjacent the outer periphery of the shoulder as best depicted inFigure 5. One or more of the said grooves will receive the wire, as willbe later more fully described.

The diameter of the base 13 is reduced above the shoulder 19 to definean extension 21 and the extension is externally threaded as shown at 22.The cap 12 is of conical outline and is formed with an internallythreaded bore 23 for receiving the threads 22 of the extension 21 toassemble the complete insulator. It will be seen that the lower face ofthe cap is formed with a planar surface 24 and an outer edge 25, thesurface 24 and edge 25 being separated by an annular groove or channel26.

It will be understood that the wire may be lodged in any one of thegrooves 20 and when the cap is drawn up on the extension 21, the wirewill pull against the pin instead of the cap. Also, the surface 24 andthe edge 25 will prevent any upward bend of the wire thereby permittingonly a downward bend. Since the downward and upward bend in extremelycold weather is the motivating factor in causing breakage, it will beappreciated that such breakage is reduced materially, if in fact noteliminated. There is thus provided a lock at each side and a mosttroublesome problem solved by this arrangement.

It should be mentioned that while I have shown two pairs of grooves 20,a lesser number could be present in the base but I have found that thegroove assemblage depicted in Figure 5 is the most desirable forcommercial purposes.

From the above description, it is deemed manifest that the presentinsulator assembly is quite simple in structural detail and allows ofthe easy and speedy attachment of the wire to the base. That area of thewire in contact with the groove in the base is fully protected from theelements and by virtue of the surfaces at the lower end of the cap, thewire cannot bend or flex upwardly thus eliminating wire breakage.

Manifestly, the insulator assembly is capable of modification in thedetails of construction and in the arrangement of parts withoutdeparture from the principle of construction and mode of operationinvolved or from the scope of the appended claim.

I claim:

An insulator assembly for use with outside electrical conductorsincluding a cylindrical body portion of plastic material having aninternally threaded bore therein for attachment to an externallythreaded support, a horizontally disposed planar shoulder on the bodyportion intermediate the ends of such body portion, the shoulder beingprovided with two pairs of diametrically opposed grooves thereinadjacent to the outer edge of the body portion, each of said groovesbeing capable of receiving an electrical conductor, an externallythreaded extension on the body portion above the shoulder, a conical capof plastic material having an internally threaded bore for cooperatingwith the threaded extension to complete the insulator, the diameter ofthe lower end of the cap being materially greater than the diameter ofthe body portion, the lower end of the cap being formed with ahorizontal planar surface which extends beyond the outer edge of thebody portion, and an annular groove in the lower end of the capintermediate the periphery of the cap and the horizontal planar surfaceso that when the cap is drawn up on the extension, the said planarsurface together with the outer edge of the cap will prevent the upwardmovement of the conductor in the groove thereby eliminating breakage ofthe conductor.

(References on following page) 3 4 References Cited in the file of thispatent 853,744 Steinberger May 14, 1907 UNITED STATES PATENTS FOREIGNPATENTS 544,778 Sproat et a1. Aug. 20, 1895 34,298 Switzerland June 30,1905 619,555 Frantz Feb. 14, 1899 5 120,418 Great Britain Nov. 5, 1918759,276 Hobert May 10, 1904

